Method for constructing power tunnel using integral hydraulic trolley

Abstract

The invention discloses an integral hydraulic trolley construction method for power tunnels, and relates to the technical field of tunnel corridor construction. The invention comprises the following contents and steps: S1, bottom plate pouring, side wall horizontal construction joint chiseling; S2, on-site binding and installation of side wall horizontal steel bars, installation and fixing of embedded parts; S3, measurement and setting out; S4, trolley in place; S5, trolley retest and acceptance; S6, installation of top plate steel bars; S7, installation of annular water stop; S8, acceptance of steel bars and embedded parts; S9, installation of external molds and end molds; S10, concrete pouring; S11, maintenance and demolding; S12, sequentially looping steps S1 to S11, and after looping 2 to 3 times, timely laying waterproofing coils, pouring waterproofing layer concrete, and layered tamping of the completed power tunnel. The invention has the characteristics of simple process, low labor intensity, and fast construction speed, and can solve the common quality problems of non-straight linearity, more joints, large misalignment, and poor appearance of the finished structure that are very easy to appear in the existing method.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel gallery construction, and more specifically, relates to a method for constructing a power tunnel using an integral hydraulic trolley. Background Art

[0002] The power tunnel is a structure for laying the main power cables of municipal engineering. It is a century-old project. Its structural cross-sectional dimensions are designed to meet the needs of maintenance personnel. It has the characteristics of small cross-sectional dimensions, long construction length and long construction period. The existing construction technology of this structure adopts the scheme of setting up brackets and assembling small templates. The construction of each section (there is a circumferential deformation joint designed every 25m in the longitudinal direction) requires manual setting up of brackets, installation of templates, debugging, dismantling and transportation, which requires a lot of labor and takes a long time, and the construction efficiency is low. At the same time, the integrity of the template is poor and it is not easy to reinforce. The cast power tunnel is very likely to have common quality problems such as linear non-straightness, many joints, large misalignment and poor appearance. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for constructing a power tunnel using an integral hydraulic trolley, which has a simple process, low labor intensity, and a fast construction speed, and can solve the common quality problems of the existing method, such as the finished product of the structure being non-straight, having many joints, large misalignment, and poor appearance.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] The method for constructing a power tunnel using an integral hydraulic trolley includes the following steps:

[0006] S1. Cast the bottom plate and roughen the horizontal construction joints of the side walls;

[0007] S2. Tie and install the horizontal reinforcement of the side walls on site, and install and fix the embedded parts;

[0008] S3, measurement and setting out;

[0009] S4, the trolley is in place;

[0010] S5, trolley retest and acceptance;

[0011] S6. Install top plate reinforcement;

[0012] S7. Install the annular waterstop;

[0013] S8. Acceptance of steel bars and embedded parts;

[0014] S9, install the outer mold and end mold;

[0015] S10, concrete pouring: Before pouring concrete, the thickness of the steel bar protective layer, the quality of formwork assembly and the cleaning of debris in the formwork need to be inspected; according to the actual situation of the project, chute pouring, bucket pouring and pump truck pouring can be adopted, and the concrete pouring vibration needs to be vibrated and compacted with an inserted vibrating rod;

[0016] S11, maintenance and demoulding;

[0017] S12. Repeat steps S1 to S11 in sequence. After 2 to 3 cycles, the completed power tunnel should be promptly covered with waterproof membrane, poured with waterproof layer concrete, and rammed in layers.

[0018] Preferably, the specific operation content and steps of step S1 are as follows:

[0019] A1. Pouring cushion concrete;

[0020] A2. After final setting, remove the surface debris and lay the bottom waterproof layer;

[0021] A3. Pour the concrete for the bottom slab waterproofing protective layer;

[0022] A4. Install the bottom plate reinforcement;

[0023] A5, embedded side wall vertical reinforcement;

[0024] A6, pre-buried horizontal construction joint water-stop steel plate and expansion joint annular rubber water-stop;

[0025] A7. Pouring base slab concrete;

[0026] A8. Roughen the horizontal construction joints of the side walls.

[0027] Preferably, the specific operation content and steps of step S3 are as follows:

[0028] B1. Measure and release the center line on the upper surface of the power tunnel floor;

[0029] B2. Place the top plate inner mold elevation control point on the bottom plate at one end of the forward direction and mark the relative height difference of the top surface of the inner mold, that is, the height difference relative to the bottom plate surface.

[0030] Preferably, the specific operation content and steps of step S4 are as follows:

[0031] C1. Start the hydraulic trolley travel system and move the trolley to a new position;

[0032] C2. Check and correct the trolley axis position, apply isolation agent to the inner mold, and install and debug the hydraulic support system.

[0033] Preferably, the specific operation content and steps of step S5 are as follows:

[0034] D1. The surveying team uses professional surveying equipment, such as a level, total station or GPS, to re-measure the position of the trolley axis and edge lines, and re-measure the elevation of the four corners of the inner mold top surface;

[0035] D2. If the acceptance fails, recalibration and retest will be carried out. If the acceptance passes, proceed to the next process.

[0036] Preferably, the specific operation content and steps of step S6 are as follows:

[0037] E1. Prepare the top plate reinforcement and the axillary diagonal reinforcement at the chamfer in advance at the reinforcement yard;

[0038] E2. After the semi-finished products are transported to the site, they should be installed according to the position, spacing and thickness of the protective layer on the design drawings, and the binding points should be firm.

[0039] Preferably, the specific operation content and steps of step S7 are as follows:

[0040] F1. The embedded waterstop extending from the bottom plate to the top plate and requiring annular closure uses B-type bars stuck in the middle of the two layers of steel bars;

[0041] F2. The joints of the water stop are welded by hot-melt welding process;

[0042] F3. Fill polyethylene foam board on both sides of the expansion joint waterstop.

[0043] Preferably, the specific operation content and steps of step S8 are as follows:

[0044] M1. According to the design drawings, the team conducts self-inspection of the steel bars, embedded parts and water stop strips of the side walls and top plates;

[0045] M2. After the team passes the self-inspection, it shall report to the technicians in the work area for review and acceptance of the steel bars, embedded parts and water stop strips of the side walls and top plates;

[0046] M3. After acceptance by the work area technician, report to the professional supervision engineer for acceptance.

[0047] Preferably, the specific operation content and steps of step S9 are as follows:

[0048] N1. Before installing the outer formwork and end formwork, the quality of the installation of the side wall and top plate reinforcement, the quality of the installation of the water stop belt and the welding of the joints, the quality of the installation of the cable bracket embedded parts, and the quality of the installation of the grounding device must be reported for inspection and acceptance;

[0049] N2. With the help of a crane, hoist the outer mold into place, and use tie rods to connect it to the inner mold as a whole for fixation according to actual conditions, or use steel pipes to support it on the foundation pit support structure alone. The end mold is fixed to the trolley with steel pipes and fasteners.

[0050] Preferably, the specific operation content and steps of step S11 are as follows:

[0051] P1. The maintenance of power tunnels adopts the measures of covering "plastic film + geotextile" to keep moisture and heat preservation. When the temperature is low, it should be covered with quilts. When the actual strength of the concrete test block under the same conditions reaches more than 75% of the design strength, it can be naturally cured;

[0052] P2. When the concrete strength reaches 2.5MPa or above, the outer formwork can be removed. When removing, first remove the tie rods, and then use a crane to remove the outer formwork piece by piece;

[0053] P3. The inner mold can be demoulded only when the actual measured strength of the concrete test block under the same conditions reaches more than 100% of the design strength.

[0054] The beneficial effects of adopting the above technical solution are:

[0055] 1) The construction process has been simplified and the process is simple;

[0056] 2) No need to set up a support, saving the cost of the support;

[0057] 3) Reduce the number of tie rods supporting the formwork and improve the appearance and waterproof quality of the structure;

[0058] 4) The time for template installation and removal is greatly shortened, the cycle time is effectively compressed, and the construction progress is improved;

[0059] 5) The labor intensity of workers is reduced and the process quality is improved;

[0060] 6) The formwork has strong integrity and the overall construction quality has been qualitatively improved;

[0061] 7) Hoisting operations and aerial operations have been greatly reduced, and construction safety risks are small;

[0062] 8) The investment in machinery and equipment during the construction process is reduced, and the investment in machinery costs is reduced;

[0063] 9) Mechanized, streamlined and standardized construction has been upgraded to a higher level;

[0064] 10) It reduces the area requirement for the working surface and improves the dirty and messy phenomenon of the working surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 A general cross-sectional structural diagram of a structure applicable to the present invention;

[0066] Figure 2 It is a construction process flow chart of the present invention;

[0067] In the figure: 1. Side wall and top plate structure; 2. Annular deformation joint waterstop; 3. Horizontal construction joint waterstop steel plate; 4. Horizontal construction joint; 5. Bottom plate structure; 6. Bottom plate waterproofing layer protective layer concrete; 7. Bottom plate waterproofing layer; 8. Cushion layer concrete structure. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0069] The cross-sectional structure applicable to the present invention is as follows Figure 1 As shown, above the cushion concrete structure 8 is the bottom slab waterproof layer 7, above the bottom slab waterproof layer 7 is the bottom slab waterproof layer protective layer concrete 6, above the bottom slab waterproof layer protective layer concrete 6 is the bottom slab structure 5, above the bottom slab structure 5 are the annularly arranged side walls and top slab structure 1, between the bottom slab structure 5 and the side wall structure there are horizontal construction joints 4 and horizontal construction joint waterstop steel plates 3, and in the middle position of the side walls and top slab structure 1 there is an annular deformation joint waterstop strip 2.

[0070] like Figure 2 As shown, the method for constructing a power tunnel using an integral hydraulic trolley includes the following steps:

[0071] Step 1: Cast the bottom slab, cast the cushion concrete, and roughen the horizontal construction joints of the side walls. After final setting, remove the surface debris, lay the bottom slab waterproof layer; cast the bottom slab waterproof layer protective layer concrete; install the bottom slab steel bars; embed the side wall vertical steel bars; embed the horizontal construction joint waterstop steel plates and the deformation joint annular rubber waterstop; cast the bottom slab concrete.

[0072] Among them, the bottom slab pouring work includes: pouring of cushion layer concrete structure 8, laying of bottom slab waterproof layer 7, pouring of bottom slab waterproof layer protective layer concrete 6, installation of bottom slab steel bars, pre-embedding of side wall vertical steel bars, pre-embedding of horizontal construction joint waterstop steel plates 3, pre-embedding and protection of annular deformation joint waterstop strips 2, and pouring of bottom slab structure 5. All these tasks require full preparation, careful implementation, and strict acceptance.

[0073] The roughening treatment of the horizontal construction joint 4 is a key link in determining the overall waterproof quality of the structure. During construction, the concrete slurry and contaminants on the surface of the construction joint must be completely removed in strict accordance with the specifications to expose fresh concrete surface and aggregate, and then the debris must be rinsed away with water.

[0074] Step 2: Tie and install the horizontal reinforcement of the side walls on site, and install and fix the embedded parts.

[0075] Among them, the vertical steel bars of the side walls have been embedded in the base plate, and before the trolley is put into place, only the remaining horizontal steel bars, cable bracket embedded parts and grounding device embedded parts need to be installed.

[0076] Before installing horizontal steel bars, comprehensive research and material cutting should be carried out based on the cycle length of the power tunnel and the spacing of the annular deformation joints, to ensure that the joint positions of the upper and lower layers of steel bars are staggered and to reduce the loss rate of steel bars. The horizontal steel bars are installed by layered marking method (i.e. marking the vertical steel bars at a certain distance according to the horizontal steel bar layer spacing) and tied and installed on site. During installation, ensure that the joints of the upper and lower layers of steel bars are staggered and the lap length of each joint meets the standard.

[0077] The embedded parts of the cable bracket are arranged on the inner surface of the side wall according to the designed layer spacing and longitudinal spacing. They are temporarily fixed with wire during installation. After being accepted by hanging a plumb line and measuring with a ruler, they are welded and fixed to the side wall steel bars with an electric welder.

[0078] The embedded parts of the grounding device include the grounding electrode angle steel and the lead flat steel passing through the side wall. The angle steel is erected at the bottom of the foundation pit outside the side wall. One end of the outer lead flat steel is welded to the grounding electrode and the other end is welded to the outer side of the waterstop steel plate at the horizontal construction joint of the side wall. One end of the inner lead flat steel is welded to the inner side of the waterstop steel plate at the horizontal construction joint of the side wall and the other end is led out of the side wall, left in the power tunnel and temporarily bent and attached to the inner surface of the side (chiseled out after demoulding).

[0079] Step 3: Measurement and layout. Before the trolley is in place, the center line must be measured and laid out on the upper surface of the power tunnel floor; the top plate inner mold elevation control point must be laid out on the floor at one end of the forward direction, and the relative height difference of the inner mold top surface must be marked, that is, the height difference relative to the floor surface.

[0080] Step 4: Put the trolley in place. Start the hydraulic trolley travel system and move the trolley to the new position; check and correct the trolley axis position, apply the isolation agent to the inner mold, and install and debug the hydraulic support system.

[0081] Step 5: Retest and accept the trolley. The surveying team uses professional surveying equipment, such as a level, total station or GPS, to retest the position of the trolley axis and sidelines, and retest the elevation of the four corners of the inner mold top surface; if the acceptance fails, recalibration and retest will be carried out, and if the acceptance passes, the next process will be carried out.

[0082] Step 6: Install the top plate reinforcement. The top plate reinforcement includes the longitudinal and transverse main reinforcements of the top plate and the axillary diagonal reinforcements at the chamfers. The top plate reinforcements and the axillary diagonal reinforcements at the chamfers should be processed in advance at the reinforcement yard; after the semi-finished products are transported to the site, they should be installed according to the position, spacing, and protective layer thickness on the design drawings, and the binding points should be firm.

[0083] Step 7: Install the annular waterstop. The waterstop at the expansion joint is a buried waterstop, which is designed to extend from the bottom plate to the top plate and needs to be closed in an annular direction. When installing the side wall and top plate reinforcement, use B-type reinforcement to simultaneously clamp the waterstop in the middle position and fix it firmly according to the requirements of the drawing design, and then fill the polyethylene foam board on both sides of the waterstop. When the annular waterstop is closed at the top plate, it needs to be lap-welded by hot-melt welding process, and the next work area will be carried out only after the joint is accepted and qualified.

[0084] Step 8: Acceptance of steel bars and embedded parts. The team will conduct self-inspection of the steel bars, embedded parts and water stop strips of the side walls and top plates according to the design drawings; after the team passes the self-inspection, they will report to the work area technician for review and acceptance of the steel bars, embedded parts and water stop strips of the side walls and top plates; after the work area technician passes the acceptance, they will report to the professional supervision engineer for acceptance.

[0085] .Step 9: Install the outer formwork and end formwork. Before installing the outer formwork and end formwork, the quality of the installation of the side wall and top plate reinforcement, the quality of the installation of the water stop belt and the welding of the joints, the quality of the installation of the cable bracket embedded parts, and the quality of the installation of the grounding device must be reported for inspection and acceptance. The acceptance shall be carried out in a three-level inspection and acceptance system (self-inspection of the team, re-inspection of the work area, and acceptance by the supervisor). The outer formwork and end formwork can only be installed after passing the acceptance. The outer formwork uses a large steel formwork that is assembled and fixed, and the end formwork uses a wooden formwork. Before installation, an isolation agent is applied first, and then the outer formwork is hoisted into place with the cooperation of a crane. The outer formwork can be fixed as a whole with a tie rod connected to the inner formwork according to the actual situation, or it can be supported on the foundation pit support structure by a steel pipe alone. The end formwork is fixed on the trolley with a steel pipe and fasteners.

[0086] Step 10: Concrete pouring. Before pouring concrete, it is necessary to inspect the thickness of the steel bar protective layer, the quality of the formwork assembly, and the cleaning of debris in the formwork. After these items are accepted, the concrete pouring can be organized.

[0087] The concrete pouring method for power tunnel can be chute pouring, bucket pouring, or pump truck pouring according to the actual situation of the project. The poured concrete needs to be vibrated and compacted using an inserted vibrating rod.

[0088] The basic principles of "symmetry on both sides, horizontal stratification, and oblique segmentation" must be followed when pouring concrete. After the top slab is poured, the surface should be finished and covered in time for moisture retention and heat preservation maintenance.

[0089] Step 11: Maintenance and demoulding; The maintenance of the power tunnel adopts the measures of covering "plastic film + geotextile" to keep moisture and heat preservation. When the temperature is low, it should be covered with quilts. When the actual strength of the concrete test block under the same conditions reaches more than 75% of the design strength, it can be naturally cured; when the concrete strength reaches more than 2.5MPa, the outer mold can be removed. When removing, first remove the pull rod, and then use the crane to remove the outer mold piece by piece; when the actual strength of the concrete test block under the same conditions reaches more than 100% of the design strength, the inner mold can be demoulded. When demoulding the inner mold, start the hydraulic station to synchronously retract the jack cylinder to demould it, or arrange workers to retract the small jack cylinder of the hydraulic support system according to the principle of "synchronization, symmetry, and circulation" to demould it (the specific operation method is selected according to the configured hydraulic system).

[0090] Step 12: Repeat steps S1 to S11 in sequence. After 2 to 3 cycles, the completed power tunnel should be promptly covered with waterproof membrane, poured with waterproof layer concrete, and rammed in layers.

[0091] When carrying out the first cycle of construction, the trolley must be assembled before step 3 (measurement and layout), and the assembly quality must be inspected after the assembly is completed. The initial assembly of the trolley and the first cycle of operation must be carried out under the guidance of professional technicians of the manufacturer.

[0092] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for constructing a power tunnel using an integrated hydraulic trolley, characterized in that: The following steps are involved: S1. Cast the bottom plate and roughen the horizontal construction joints of the side walls; S2. Tie and install the horizontal reinforcement of the side walls on site, and install and fix the embedded parts; S3, measurement and setting out; S4, the trolley is in place; S5, trolley retest and acceptance; S6. Install top plate reinforcement; S7. Install the annular waterstop; S8. Acceptance of steel bars and embedded parts; S9, install the outer mold and end mold; S10, concrete pouring: Before pouring concrete, the thickness of the steel bar protective layer, the quality of formwork assembly and the cleaning of debris in the formwork need to be inspected; according to the actual situation of the project, chute pouring, bucket pouring and pump truck pouring can be adopted, and the concrete pouring vibration needs to be vibrated and compacted with an inserted vibrating rod; S11, maintenance and demoulding; S12, repeating steps S1 to S11 in sequence, and after 2 to 3 cycles, promptly laying waterproof membranes and pouring waterproof layer concrete on the completed power tunnel, and tamping and filling in layers; The specific operation content and steps of step S3 are as follows: B1. Measure and release the center line on the upper surface of the power tunnel floor; B2. Place the top plate inner mold elevation control point on the bottom plate at one end of the forward direction and mark the relative height difference of the top surface of the inner mold, that is, the height difference relative to the bottom plate surface; The specific operation content and steps of step S4 are as follows: C1. Start the hydraulic trolley travel system and move the trolley to a new position; C2. Check and correct the trolley axis position, apply the isolation agent to the inner mold, and install and debug the hydraulic support system; The specific operation content and steps of step S6 are as follows: E1. Prepare the top plate reinforcement and the axillary diagonal reinforcement at the chamfer in advance at the reinforcement yard; E2. After the semi-finished products are transported to the site, they shall be installed according to the position, spacing and thickness of the protective layer on the design drawings, and the binding points shall be firm; The specific operation content and steps of step S7 are as follows: F1. The embedded waterstop extending from the bottom plate to the top plate and requiring annular closure uses B-type bars stuck in the middle of the two layers of steel bars; F2. The joints of the water stop are welded by hot-melt welding process; F3. Fill polyethylene foam board on both sides of the expansion joint waterstop.

2. The method for constructing a power tunnel using an integrated hydraulic trolley according to claim 1, characterized in that: The specific operation content and steps of step S1 are as follows: A1. Pouring cushion concrete; A2. After final setting, remove the surface debris and lay the bottom waterproof layer; A3. Pour the concrete for the bottom slab waterproofing protective layer; A4. Install the bottom plate reinforcement; A5, embedded side wall vertical reinforcement; A6, pre-buried horizontal construction joint water-stop steel plate and expansion joint annular rubber water-stop; A7. Pouring base slab concrete; A8. Roughen the horizontal construction joints (4) of the side walls.

3. The method for constructing a power tunnel using an integrated hydraulic trolley according to claim 1, characterized in that: The specific operation content and steps of step S5 are as follows: D1. The surveying team uses professional surveying equipment, such as level, total station or GPS, to re-measure the position of the trolley axis and edge lines, and re-measure the elevation of the four corners of the inner mold top surface; D2. If the acceptance fails, recalibration and retest will be carried out. If the acceptance passes, proceed to the next process.

4. The method for constructing a power tunnel using an integrated hydraulic trolley according to claim 1, characterized in that: The specific operation content and steps of step S8 are as follows: M1. According to the design drawings, the team conducts self-inspection of the steel bars, embedded parts and water stop strips of the side walls and top plates; M2. After the team passes the self-inspection, it shall report to the technicians in the work area for review and acceptance of the steel bars, embedded parts and water stop strips of the side walls and top plates; M3. After acceptance by the work area technician, report to the professional supervision engineer for acceptance.

5. The method for constructing a power tunnel using an integrated hydraulic trolley according to claim 1, characterized in that: The specific operation content and steps of step S9 are as follows: N1. Before installing the outer formwork and end formwork, the quality of the installation of the side wall and top plate reinforcement, the quality of the installation of the water stop belt and the welding of the joints, the quality of the installation of the cable bracket embedded parts, and the quality of the installation of the grounding device must be reported for inspection and acceptance; N2. With the help of a crane, hoist the outer mold into place, and use tie rods to connect it to the inner mold as a whole for fixation according to actual conditions, or use steel pipes to support it on the foundation pit support structure alone. The end mold is fixed on the trolley with steel pipes and fasteners.

6. The method for constructing a power tunnel using an integrated hydraulic trolley according to claim 1, characterized in that: The specific operation content and steps of step S11 are as follows: P1. The maintenance of power tunnels adopts the measures of covering "plastic film + geotextile" to keep moisture and heat preservation. When the temperature is low, it should be covered with quilts. When the actual strength of the concrete test block under the same conditions reaches more than 75% of the design strength, it can be naturally cured; P2. When the concrete strength reaches 2.5MPa or above, remove the outer formwork. First remove the tie rods, and then use a crane to remove the outer formwork piece by piece. P3. When the actual strength of the concrete test block under the same conditions reaches more than 100% of the design strength, the inner mold will be demoulded.

Images